Ancient Greenland Rocks Discovered in Iceland Offer Breakthrough Insights into Late Antique Ice Age
April 24, 2025 Reykjavik, Iceland — A groundbreaking study published this month has provided compelling new evidence about the Late Antique Ice Age (LALIA)—a mysterious period of sudden climate cooling that began around 536 AD and lasted through 660 AD. The discovery centers on ancient Greenland rocks found embedded in Icelandic cliffs, believed to have been carried there by icebergs over 1,500 years ago.
The study, conducted by researchers Christopher Spencer, Ross Mitchell, and Thomas Gernon, and published in the journal Geology, offers unprecedented geological evidence tying glacial and iceberg activity to the climate anomalies of the LALIA period.
Mysterious Climate Collapse Revisited
LALIA has long puzzled historians and scientists alike. Previously, it was believed to be triggered by a series of massive volcanic eruptions beginning around 540 AD. These eruptions expelled vast quantities of ash and aerosols into the atmosphere, reducing sunlight and plunging the Northern Hemisphere into a prolonged cold spell.
Historical records from the time speak of darkened skies, crop failures, and mass migrations, with some scholars even linking the climatic upheaval to sociopolitical shifts like the fall of the Western Roman Empire and barbarian invasions.
Greenland Rocks Out of Place in Iceland
While exploring cliffs along Iceland’s western coast, the research team noticed unusual rocks embedded in the landscape—rock types inconsistent with Iceland’s native geology. After collecting samples, the team used microscopic zircon crystal analysis to determine the rocks’ origin.
The zircon crystals—effectively geological “time capsules”—revealed that the rocks originated in Greenland, and were most likely transported via icebergs calved from ancient glaciers, which increased in activity due to the sharp temperature drops during the LALIA.
What This Means for Climate Science
This discovery provides the first direct physical evidence linking increased glacial activity with the Late Antique Ice Age, confirming that iceberg drift extended farther than previously believed. It supports models suggesting that the Northern Hemisphere’s cooling was not only atmospheric but also glacially dynamic.
“This is a powerful piece of the climate puzzle,” said co-author Ross Mitchell. “It shows us how dramatically Earth’s systems can respond to sudden volcanic and environmental changes.”
Implications for the Present and Future
Beyond its historical significance, the study offers vital implications for modern climate research. It demonstrates how rapid climate shifts—triggered by natural or anthropogenic causes—can have cascading effects across glacial systems, ocean currents, and global weather patterns.
The researchers suggest that understanding such ancient events may help better predict and mitigate the effects of future climate disruptions, especially in regions heavily influenced by polar and glacial activity.
